another forum I use gives an excellent explanation on this. It also provides a spread sheet that will tell you exactly how much torque it will take to get the same times (0-60, 1/4) with a heavier wheel.
PM if you would still like it.
As a matter of the fact, the file it self is the same one as the mazda6tech site. none the less, they have a discussion you maybe interisted in. I don't think anyone has real world times or numbers, but they will provide you with a nice hypothetical one!
Dude..Flat out..If you reduce unsprung weight..and reduce rotational mass..your Response will be better..Period.
Its the same reason I just dropped over $2g's on a set of wheels for my Motocycle...For every ounce of rotational mass I can drop from the bikes wheels..Its like dropping 4x that weight from the sprung(non moving) part of the bike.
At speed..each once of weight I drop from my rotational mass will be like dropping 25lbs. at 100MPH....SO for me...Dropping just 20 oz. from my wheels would be like shedding 500lbs. at 100MPH.
Which is a hell of a difference.
Think of it this way...We buy lightweight flywheels why?
TO drop Rotational Mass from the engine...Guess what..your wheels are still rotational mass.
Connected to the Drivetrain.
Now...Not all wheels are created equal...two identically weighted wheels can react differenty depending on the weights distribution.
If the wheel drops the weight from the outer RIm shell area..vs losing it around the Hub..It will perform better than the wheel that dropped most of its weight at the hub.
It really is Physics man.
Dropping 4-5 lbs a wheel will take 8-10 Lbs. of rotational mass from your drivetrain which will help you out..Not to mention the fact that you drop apprx. 20 lbs from the cars sprug weight.
OK..I just made a point of how it helps us on our bikes...and the fact that it will in fact help his performance.Don't get me wrong, I agree. but 4-5lbs a wheel is going to be more like 200lbs of unsprung weight. check the excel worksheet posted on the mazda6tech site.
Well thats a no brainer..If your purely going for Speed and performance..But who wants a tiny ugly whel ..No one....But a true race car...You have to have a Happy medium..a balance.I don't think the agrument was rather or not it helped at all; but "how much" does it help and is it really worth the $$$?
From what I've gathered, to get some real improvement from the unsprung weight side of things, it would be alot more beneficial to get a set of light weight (14-16lbs) 17's vice 18's that weigh only 4lbs less per wheel. 17's are of course going to be a little less $$$ as well![]()
Well thats a no brainer..If your purely going for Speed and performance..But who wants a tiny ugly whel ..No one....But a true race car...You have to have a Happy medium..a balance.
And Yes..If you want new wheels for the looks..and you can drop weight at the same time..yes..you its worth it...It has benefits of both worlds.
Performance and looks.
My dilemma is whether to buy a set of 23 pound wheels and Cobb springs now or buy 19 pound wheels now and have to wait for Christmas (or maybe next tax season) for the springs. I need to get rims for the summer tires I already have and can't use until I get 8" rims for them. Hence my question. Is the performance gain of the 4 pounds worth spending the summer without the springs? From what I can tell from that spread sheet, it appears that the gain from 4 pounds is not worth fussing over. Yes, there would be an improvement, and I might even notice it, but it wouldn't be enough to outweigh the handling improvement I'll get from the springs. I'm going to get the heavier rims and springs now.
Thank you all for the feedback.
My dilemma is whether to buy a set of 23 pound wheels and Cobb springs now or buy 19 pound wheels now and have to wait for Christmas (or maybe next tax season) for the springs. I need to get rims for the summer tires I already have and can't use until I get 8" rims for them. Hence my question. Is the performance gain of the 4 pounds worth spending the summer without the springs? From what I can tell from that spread sheet, it appears that the gain from 4 pounds is not worth fussing over. Yes, there would be an improvement, and I might even notice it, but it wouldn't be enough to outweigh the handling improvement I'll get from the springs. I'm going to get the heavier rims and springs now.
Thank you all for the feedback.
If you want to get right down to it, shop for the lightest tires. They have more of an affect on rotational mass as they are furthest from the hub. Edge racing lists tire weights.
which rims are you considering? i have been searching for a set of rims for the last 3 months now so maybe i can send you to a cheaper site? or find you similar rims for less??
either way I am interisted to see what your two choices are